Tack-driving implement



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UNITED STATES MATTHIAS BROCK, BOSTON,

COPELAND LASTlNG PATENT TACK-DR|VING IMPLENI ENT.

PEIFICATION forming part of Letters Patent No. 516,074, dated March 6, 1894.

Application ned my 20,1891. serial No. 400,081.

.T9 @ZZ whom if' may concern:

Be it known that I, MATTHIAS Beeck, of Boston, county of Sudolk, State of .Massach usetts, have invented an Improvement in Tack- Driving Implements, of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention is intended as an improvement upon the class of tack driving implements representedin United States Patent No. 306,671, wherein the driver is connected with a vertically reciprocatingplun ger, and a lever or I5 device acted upon bythe driver or a part moving in unison with it actuates the feeding mechanism to feed the strip, the said lever having such a construction in accordance with my invention that the feeding device will not 2o act to engage a tack to move the tack strip or to engage a part of the tack strip to feed a new tack into position until after the driver has made a driving descent.

Figure 1 represents in side elevation a tack z 5 driving implement embodying my invention. Fig. 2 is a section thereof in the dotted line fc, and Fig. 3 is a section in the dotted line looking downwardly. v

ln the said drawings, A represents a suit able handpiece, shell or case which contains a driver bar A having secured to it a driver A3, the said bar being surrounded by a spiral spring A2 which normally elevates it, keeping the driver up as represented in the draw- 3 5 ings.

The lower part of the implement is shaped to receive a slide 6 provided with a pawl E having its point Il extended into the head E of the machine, to which is connected the nail 4o tube or nose D. The head E is provided with a longitudinal guide-Way through which is fed the tack strip from which the tacks are out od singly to be driven through the hole 10, see Fig. 3, in the nose D.

The tack strip used herein may be of any usual or suitable kind.

The pointe of the feed device F 1s normally kept pressed toward the tack strip, so as to engage the bodies of the tacks or other part 5o of the tack strip in usual manner by a spiral y its upper `the driver spring f4 on a stud f3.

(No model.)

The parts so far described are and may be substantially as in United States Patent No. 306,671, granted to me October 14, 1884, Wherein like parts are designated by like letters and 5 5 figures.

In this present instance of my invention I have provided the tack driving implement with a lever B having its fulcrum at B near end and near the upper end of the 6o hand-piece A of the implement. The lower end of the lever B is slotted as at 12'to embrace a block 13 mounted loosely on a pin 14- carried by the slide bar 6, which constitutes part of the feeding mechanism, the other part being the pawl E. The driver bar A' is provided with a suitable roller or other stud b, which enters a slot b', b2 in the lever B intermediate its fulcrum and its slotted lower end, the part l1 of the slot being essentially parallel 7o with the longitudinal center of the lever and in line with its pivot and forked end, and the part b2 of the slotbeing directed away from the point 4 of the feeding device, that is to say, said part b2 is offset from part b in a di- 75 rection away from the pivotal point of the feeding device or at an obtuse angle to the part b', and its shape is such that the lever B will not be vibrated far enough in the direction of the arrow 2, (see Fig. l) to carry So the point i of the pawl to the rear of a tack by or through the action of the roll b in the slot of the lever until the driver bar has had imparted to it a driving stroke, that is, a stroke low enough to effect the driving of a tack from the nail tube or nose D, as it is only when the said roll is Way down, due to a full driving stroke of the driver bar, that the said roll enters the angular or inclined part b2 of the slot, and it is only when the roll 9o is in that part of the slot that the feeding device F is sufficiently retracted or moved backwardly to come properly into engagement with the body of a tack or a part of the tack strip so that at the next complete ascent of bar the lever B Will be moved suffi'- ciently far to the left, see Fig. 1, or in the direction of the arrou7 3, to feed a tack forward in proper position under the then elevated driver and over the passage 10 in the nail tube roo or nose.

ln the class of tack driving implement referred to, great trouble has been experienced in practice due to improper feeding of the tack strip, that is, the feeding device engages and moves the strip when the driver bar makes but a partial descent, and as a result thereof, it frequently happens that two or more tacks are partially driven into the hole in the nail tube or nose, and the latter becomes so clogged that the operator has to stop work and punch out the nails or tacks, but by means of my improvement it is impossible to clog the nailtube or passage and under no circumstances is it found necessary to lose the use of the implement so long as it is supplied with tacks.

It will be noticed that I gain this my invention Without adding to the parts of the machine, but to effect my improved operation and the advantages above stated, I have been obliged to fnlcrum the lever B in a different position and differently With relation to its length and to materially alter the shape of the cam slot so as to actuate the lever ina different time and order With relation to the other parts of the implement.

Having described my invention, what I claim, and desire -to secure by Letters Patent, 1s-

The herein described tack-driving implement, it consisting of ya shell or case, a reciprocating driver therein, a lever pivoted upon said shell or case, a feeding device comprising a slide-bar connected with the lower end of said lever, the said lever being provided with a cam-slot b', b2, between its pivotal end and its end engaged with the feeding device, the portion b of said cam-slot being in line with the pivotal end and the lower end of the said lever, and the portion b2 of said cam-slot being off-set in a direction away from the pivotal point of the feeding device and obliqnely to the portion b', and a roll on the driver engaging said cam-slot to vibrate the lever, substantially as and for the purpose set forth.

Iny testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

MATTHIAS BROCK.

Vlitnesses:

G. W. GREGORY, EMMA J. BENNETT. 

